Both Nissan and Mazda on Thursday held steady their earnings forecasts for the fiscal year started April despite posting slight revenue growth in the April- June quarter, underlining the automakers' cautious outlook, Dow Jones reported. The news agency said the companies' conservative views reflect signs of decreasing demand from the US market at a time when the car market back home in Japan remains sluggish. Japanese car exports to the US decreased 2.3% in June, the second straight month of falls, Dow Jones noted, citing industry data.